Nog has better wrestling than Couture (as he showed when he threw Randy around), and I think he'd stand a much better chance against Lesnar. And it has nothing to do with his size.
I don't think so.
Mir is a top heavyweight but he has weaknesses, which everyone has pointed out. I don't think any has really said he's going to dominate, so the original message of the thread is pointless. Other than Brock, I can't see any HW dominating.
Mir - Tooled Nog and Kongo standing up but Brock is clearly his kryptonite.
JDS - he has the potential to KO his way to the title, so long as a wrestler doesn't take him down and control him. If he became champ, a wrestler would soon do this.
Valesquez - Can be neutralised by the bigger versions of him.
Big Nog - Could get dominated by wrestlers and regardless of illness, got his ass completely handed to him by Mir. Beating Randy was good but Randy couldn't deal with the monsters of the division today. Nog still has some proving to do, his fight against Cain will show a lot.
Carwin - In my opinion the most overrated of the lot, especially in terms of standup. Very heavy hands but could be on the receiving end if he boxes with someone like Nog. I think Mir will beat Carwin.
Lesnar - the only one I can see dominating.
After Lesnar the division is wide open.